From 5b1a3d50e618bb0ee9a7a095d65b24f26b633b00 Mon Sep 17 00:00:00 2001
From: Maximilian Goldstein <max.goldstein@qt.io>
Date: Tue, 13 Jul 2021 11:58:26 +0200
Subject: qv4codegen: Provide more accurate SourceLocations

Previously the source locations in the bytecodegenerator were often imprecise due to them not being updated often enough.
This change makes sure that FieldMemberExpressions and IdentifierExpressions report more accurate locations instead.

Change-Id: Ib53cda5cc927551c25ed32ed34d4b65d82f5e199
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>
---
 src/qml/compiler/qv4codegen.cpp | 21 +++++++++++++++++----
 src/qml/compiler/qv4codegen_p.h | 11 ++++++++---
 2 files changed, 25 insertions(+), 7 deletions(-)

(limited to 'src/qml/compiler')

diff --git a/src/qml/compiler/qv4codegen.cpp b/src/qml/compiler/qv4codegen.cpp
index 7787f1541a..2b4168e155 100644
--- a/src/qml/compiler/qv4codegen.cpp
+++ b/src/qml/compiler/qv4codegen.cpp
@@ -1293,7 +1293,9 @@ bool Codegen::visit(ArrayMemberExpression *ast)
         if (arrayIndex == UINT_MAX) {
             auto jumpLabel = ast->isOptional ? m_optionalChainLabels.take(ast) : Moth::BytecodeGenerator::Label();
 
-            setExprResult(Reference::fromMember(base, str->value.toString(), jumpLabel, targetLabel));
+            setExprResult(Reference::fromMember(base, str->value.toString(),
+                                                ast->expression->firstSourceLocation(), jumpLabel,
+                                                targetLabel));
             return false;
         }
 
@@ -2489,9 +2491,10 @@ bool Codegen::visit(FieldMemberExpression *ast)
         return false;
     }
 
-    setExprResult(Reference::fromMember(base, ast->name.toString(),
-                                        ast->isOptional ? m_optionalChainLabels.take(ast) : Moth::BytecodeGenerator::Label(),
-                                        label.has_value() ? label.value() : Moth::BytecodeGenerator::Label()));
+    setExprResult(Reference::fromMember(
+            base, ast->name.toString(), ast->firstSourceLocation(),
+            ast->isOptional ? m_optionalChainLabels.take(ast) : Moth::BytecodeGenerator::Label(),
+            label.has_value() ? label.value() : Moth::BytecodeGenerator::Label()));
 
     return false;
 }
@@ -2625,12 +2628,14 @@ Codegen::Reference Codegen::referenceForName(const QString &name, bool isLhs, co
         r.isReferenceToConst = resolved.isConst;
         r.requiresTDZCheck = resolved.requiresTDZCheck;
         r.name = name; // used to show correct name at run-time when TDZ check fails.
+        r.sourceLocation = accessLocation;
         return r;
     }
 
     Reference r = Reference::fromName(this, name);
     r.global = useFastLookups && (resolved.type == Context::ResolvedName::Global || resolved.type == Context::ResolvedName::QmlGlobal);
     r.qmlGlobal = resolved.type == Context::ResolvedName::QmlGlobal;
+    r.sourceLocation = accessLocation;
     if (!r.global && !r.qmlGlobal && m_globalNames.contains(name))
         r.global = true;
     return r;
@@ -4640,6 +4645,10 @@ QT_WARNING_POP
                 return;
             }
         }
+
+        if (sourceLocation.isValid())
+            codegen->bytecodeGenerator->setLocation(sourceLocation);
+
         if (!disable_lookups && global) {
             if (qmlGlobal) {
                 Instruction::LoadQmlContextPropertyLookup load;
@@ -4659,6 +4668,10 @@ QT_WARNING_POP
     case Member:
         propertyBase.loadInAccumulator();
         tdzCheck(requiresTDZCheck);
+
+        if (sourceLocation.isValid())
+            codegen->bytecodeGenerator->setLocation(sourceLocation);
+
         if (!disable_lookups && codegen->useFastLookups) {
             if (optionalChainJumpLabel->isValid()) { // If we got a valid jump label, this means it's an optional lookup
                 auto jump = codegen->bytecodeGenerator->jumpOptionalLookup(codegen->registerGetterLookup(propertyNameIndex));
diff --git a/src/qml/compiler/qv4codegen_p.h b/src/qml/compiler/qv4codegen_p.h
index f4a7bf4465..58f46f9313 100644
--- a/src/qml/compiler/qv4codegen_p.h
+++ b/src/qml/compiler/qv4codegen_p.h
@@ -279,14 +279,18 @@ public:
             r.name = name;
             return r;
         }
-        static Reference fromMember(const Reference &baseRef, const QString &name,
-                                    Moth::BytecodeGenerator::Label jumpLabel = Moth::BytecodeGenerator::Label(),
-                                    Moth::BytecodeGenerator::Label targetLabel = Moth::BytecodeGenerator::Label()) {
+        static Reference
+        fromMember(const Reference &baseRef, const QString &name,
+                   QQmlJS::SourceLocation sourceLocation = QQmlJS::SourceLocation(),
+                   Moth::BytecodeGenerator::Label jumpLabel = Moth::BytecodeGenerator::Label(),
+                   Moth::BytecodeGenerator::Label targetLabel = Moth::BytecodeGenerator::Label())
+        {
             Q_ASSERT(baseRef.isValid());
             Reference r(baseRef.codegen, Member);
             r.propertyBase = baseRef.asRValue();
             r.propertyNameIndex = r.codegen->registerString(name);
             r.requiresTDZCheck = baseRef.requiresTDZCheck;
+            r.sourceLocation = sourceLocation;
             r.optionalChainJumpLabel.reset(new Moth::BytecodeGenerator::Label(jumpLabel));
             r.optionalChainTargetLabel.reset(new Moth::BytecodeGenerator::Label(targetLabel));
             return r;
@@ -382,6 +386,7 @@ public:
         quint32 isVolatile:1;
         quint32 global:1;
         quint32 qmlGlobal:1;
+        QQmlJS::SourceLocation sourceLocation = QQmlJS::SourceLocation();
         QSharedPointer<Moth::BytecodeGenerator::Label> optionalChainJumpLabel;
         QSharedPointer<Moth::BytecodeGenerator::Label> optionalChainTargetLabel;
 
-- 
cgit v1.2.3